Etna's January 2011 eruption provided an excellent
opportunity to test the ability of Meteosat Second Generation
satellite's Spinning Enhanced Visible and InfraRed
Imager (SEVIRI) sensor to track a short-lived effusive
event. The presence of lava fountaining, the rapid expansion
of lava flows, and the complexity of the resulting flow field
make such events difficult to track from the ground. During
the Etna's January 2011 eruption, we were able to use
thermal data collected by SEVIRI every 15 min to generate
a time series of the syn-eruptive heat flux. Lava discharge
waxed over a ~1-h period to reach a peak that was first
masked from the satellite view by a cold tephra plume and
then was of sufficient intensity to saturate the 3.9-μm
channel. Both problems made it impossible to estimate
time-averaged lava discharge rates using the syn-eruptive
heat flux curve. Therefore, through integration of data
obtained by ground-based Doppler radar and thermal cameras,
as well as ancillary satellite data (from Moderate Resolution
Imaging Spectrometer and Advanced Very High
Resolution Radiometer), we developed a method that
allowed us to identify the point at which effusion stagnated,
to allow definition of a lava cooling curve. This allowed
retrieval of a lava volume of ~1.2×106 m3, which, if emitted
for 5 h, was erupted at a mean output rate of ~70 m3 s−1. The
lava volume estimated using the cooling curve method is
found to be similar to the values inferred from field
measurements.